    [Patent document 1] JP-H5-298013 A    [Patent document 2] JP-H7-298013 A    [Patent document 3] JP-H7-319618 A (corresponding to U.S. Pat. No. 5,877,749)    [Patent document 4] JP-2001-43011 A (corresponding to U.S. Pat. No. 6,360,622)    [Patent document 5] JP 2002-157063 A    [Patent document 6] JP-2006-126997 A    [Patent document 7] JP-2006-252093 A
Patent documents 1 to 6 describe manipulation input apparatuses for in-vehicle apparatuses such as a car navigation apparatus. In manipulation input apparatuses, a load of manipulation input applied to an input section is detected by several load sensors such as strain gauges accompanying the input section; the direction and position of the manipulation input is determined based on detection values from the load sensors.
Furthermore, for example, Patent document 6 describes a manipulation input apparatus, in which pressure sensors are arranged at the four corners of the rear surface of a touch panel member, and not only the position (X-Y coordinates) of the depressed touch panel member but also the downward pressure (+Z direction) is detected based on the load detected by the pressure sensors. In addition, Patent document 7 describes a manipulation input apparatus in which calculation of a contact force of a finger or touch pen with a touch panel member uses information on moment generated on the touch panel member by friction between the finger or the like and the touch panel member.
In the manipulation input apparatus of Patent document 6, the depression load or pressing-down load (+Z direction) against the touch panel member can be detected, but the pulling-up load (−Z direction) against the touch panel member cannot be detected. In addition, in the manipulation input apparatus of Patent document 7, the information on moment generated on the touch panel member is used, thus, the ingredient of load which acts on −Z direction is indirectly used in calculating the contact force; however, the load which acts on −Z direction of the touch panel member is not directly used. As a result, the conventional manipulation input apparatuses typically use only the depression load (+Z direction) against the touch panel member substantively, thus tending to restrict manipulation modes in the touch panel member.